Roll decreasing structure of a suspension for the front and dead axles of a commerical vehicle

ABSTRACT

A roll decreasing structure of a suspension for the front and dead axles of a commercial vehicle, wherein an axle is inserted into the body of a mounting member mounted at a frame, a base arm mounted with wheels is attached to an external side of the axle via a key and the axle is mounted at the other end of the axle with a torsion bar case to which an end of a torsion bar of a straight spring steel is mounted by way of serration method.

FIELD OF THE INVENTION

[0001] The present invention relates to suspension for the front and dead axles of a commercial vehicle, and more particularly, to a roll decreasing structure adapted with a torsion bar.

BACKGROUND OF THE INVENTION

[0002] Generally, suspension for a commercial vehicle utilizes many elements, such as leaf springs, leaf spring-mounted brackets, shackles, u-bolts, and the like. The axles and the leaf springs are typically heavy in weight. Furthermore, this system is a non-independent suspension such that the ride, comfort, and safety of the vehicle are inferior.

[0003] Independent suspension systems for the front and dead axles typically include a mounting member mounted at a frame, a base arm rotatably mounted at the mounting member, and a coil spring installed between the base arm and the mounting member. The coil spring is connected to the base arm and the mounting member for generating a torsional reaction force when the base arm is rotated.

[0004] The mounting member is formed with a bracket, above, and with an axle at a lateral surface. The bracket is mounted to the frame via bolts and nuts. A boss of the base arm attaches to the axle, while the base arm is formed at the other end with a spindle for mounting the wheels thereto.

[0005] The weight of the vehicle is thus supported by the coil spring. The independent suspension system absorbs vibration and shock via the coil spring, thereby, coping with the up and down movement of the vehicular body while the vehicle is in motion.

[0006] Furthermore, vehicles are typically equipped with a stabilizer bar which serves to reduce the difference in height among the wheels when the vehicle turns or runs over rough terrain. Therefore, reducing the rolling and improving the stability of the vehicle, and particularly the turning stability.

[0007] Typically, a stabilizer bar is bent at both sides to a “U” shape and is formed at both tip ends with flat bolt holes for connecting to brackets. The stabilizer bar is further equipped with a stabilizer rod in order to be secured at a midsection to a vehicular body.

[0008] Furthermore, the stabilizer rod is formed with semi-circular up/down brackets for fitting to the stabilizer bar and rubber bushes. An upper side of the stabilizer rod, mounted to the frame, is attached with a number of parts such as rubber bushes, washers, and the like. In use, the number of parts is large, resulting in an increase of time and effort in the assembly process. Also, the rubber bushes typically wear out, generating a squeaky-type sound and the formation of cracks at the connecting parts, etc.

[0009] In consideration of the above problems, the roll decreasing structure thus described is not appropriate for a suspension for the front and dead axles of a commercial vehicle.

SUMMARY OF THE INVENTION

[0010] In an embodiment of the present invention, mounting members attach to a vehicle frame and base arms mount to the wheel unit. The free ends of the mounting members and base arms are interconnected by a coil spring. The base arms move in relation to the wheel incurring vibration and impact forces. The vibration and impact forces are then transferred to the coil spring. Thus, repulsive forces are generated within the coil spring from torsion of the coil spring by the movement of the base arms. A torsion bar is also provided to transmit forces generated at one wheel into a mutual turning effect to the axle oppositely positioned on the other side of the vehicle from the at both sides of the vehicular body.

[0011] In use, the torsion bar interconnects two axles mounted with the base arms at their respective external sides, where the two axles are rotatably mounted to the mounting members at both sides. As a result, the rotating phase difference of the base arms at both sides are restricted by the torsion bar, thereby reducing the height difference between the two wheels and decreasing rolling of the vehicle body.

[0012] Furthermore, the torsion bar according to the present invention is formed in a straight shape, thereby becoming simple in form and mounting structure, and reduced in weight and in the number of parts for easy assembly.

[0013] Still another advantage in that the reduced number of parts and reduced cost and non-usage of the rubber bush in the conventional stabilizer rod enable to increase the life of durability and decrease maintenance costs.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The features and advantages of the present invention will be better understood by reference to the following detailed description taken in conjunction with the accompanying drawings in which:

[0015]FIG. 1 is a plan view of an independent suspension system of a commercial vehicle according to an embodiment of the present invention;

[0016]FIG. 2 is an enlarged view of the principal parts of FIG. 1; and

[0017]FIG. 3 illustrates a longitudinal sectional view of FIG. 2 and a right side view of the same.

DETAILED DESCRIPTION OF THE INVENTION

[0018] As shown in FIGS. 1-3, a mounting member 100 is formed with a body 110 and a bracket 120 that are disposed at an upper side of a body 110. The bracket 120 is formed with bolt holes 121. The mounting member 100 is mounted to a frame (F) via bolts (B) and nuts (N) through the bracket 120.

[0019] The body 110 of the mounting member 100 is formed with through holes 113 through which an axle 500 is inserted from the inside of the vehicular body toward the exterior. The body 110 is formed at an inner circumferential surface thereof with a grease passage 114, and a grease inlet hole 115. The grease inlet hole 115 is formed at appropriate places of the body 110 for grease to be poured into the grease passage 114. Sealing (S) are adhered to the axle 500 and installed at both ends of the inner circumferential surface the body 110 for preventing oil from leaking outside.

[0020] A hitching jaw 510 is formed at the end of the axle 500, toward the external side of the vehicular to prevent the axle 500 from slipping outwardly from the body 110 of the mounting member 100. A key groove 520 is formed at an outer circumferential surface of the axle 500 where the base arm 200 is mounted.

[0021] A key groove is also formed at an inner surface of a boss 210 corresponding to the key groove 520 when the boss 210 of the base arm 200 is inserted onto the axle 500. The key groove establishes that the base arm 200 and the axle 500 are integrally rotated when a key (K) is inserted into the key groove. The base arm 200 is formed at the other end thereof with a spindle 220 on which wheels (W) are mounted.

[0022] A coil spring 300 is inserted into the axle 500 before the boss 210 of the base arm 200 is mounted to the axle 500. Both ends of the coil spring 300 are respectively inserted into round holes 112 at the protruder 111 (FIG. 3) defined at the body 110 of the mounting member 100 and at the protruder 211 (FIG. 2) defined at the boss 210 of the base arm 200. Both ends of the coil spring 300 are also bent so that they should not slip out of position.

[0023] Once the key (K) is inserted, a cover 400 having a larger diameter than the axle 500 is mounted by a bolt (B′), through bolt holes 530, to an external end surface of the axle 500. This prevents the base arm 200 from being separated from the axle 500.

[0024] The axle 500 is mounted at an inner end surface thereof with a torsion bar case 600 via a bolt (B″). The torsion bar case 600 is cylindrically shaped and formed thereunder with a flange. The torsion bar case 600 is coupled with a straight torsion bar 700. In a preferred embodiment the torsion bar 700 is made of spring steel and coupled with the torsion bar case 600 by a serration method, such that circumferential movement is restricted therebetween.

[0025] The above-mentioned structure is also applied to a suspension system at the wheel (W) of the opposite side of the vehicle. Therefore, both ends of the torsion bar 700 are mounted, on opposite ends with two axles 500 inserted into a mounting member 100 at both the left and a right side of the vehicle. Thus, in use, the rotating phase difference of the base arms at both sides of the vehicle are restricted by the torsion bar, thereby reducing the height difference between the two wheels and decreasing rolling of the vehicle body.

[0026] Hereinafter, the operation of the present invention will be described.

[0027] When the base arm 200 is rotated by the bouncing or movement of the vehicular body, the axle 500 is rotated at the same angle as that of the base arm 200. This transfer in movement between the base arm 200 and the axle 500 is due to the key (K). The amount of rotation is then transmitted through the torsion bar case 600 and to the torsion bar 700.

[0028] When the position of the wheels at both sides of the vehicle are changed, the rotating direction and angles of the base arms 200 at both sides of the vehicle also change. However, when the torsion bar 700, interconnecting two axles 500 on both sides of a vehicle restrict the axles 500 from moving, the angle difference between the base arms 200 at both sides of the vehicle is reduced. Thereby, the relative position difference between the two wheels is decreased. As a result, the rolling of a vehicle can be restricted to thereby provide stability to a vehicle in motion.

[0029] The torsion bar 700 can be twisted within the scope of spring resilience to allow wheels at both sides to move independently as much as the amount of the twist, such that the suspension system dose not lose the characteristic of an independent suspension.

[0030] As apparent from the foregoing, there is an advantage in the roll decreasing structure of a suspension for the front and dead axles of a commercial vehicle. Thus, an appropriate amount of roll decreasing can be achieved in the suspension of the front and dead axles of a commercial vehicle utilizing the torsional reaction force of a spring. As a result, the rotating stability of a vehicle can be enhanced to decrease the instability felt by a driver relative to the rolling of a vehicle that occurs when the vehicle is in motion.

[0031] While this invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. 

What is claimed is:
 1. A roll decreasing structure of a suspension for the front and dead axles of a commercial vehicle, comprising: a mounting member configured to be coupled to a frame; base arms coupled at wheels and interconnected to said mounting member by a coil spring wherein vibration and impact are absorbed by repulsive force in response to torsion of said coil spring in relation to rotation of said base arm; and a straight torsion bar configured to interconnect axles mounted at said base arms for transmitting a mutual turning effect.
 2. The structure as defined in claim 1, wherein said mounting member comprises a body defining a hole therethrough into which an axle is correspondingly inserted, and wherein said base arm is fixed toward an external end of said axle, and a torsion bar case is mounted toward an inner end of said axle, and said torsion bar case is coupled by an end of the straight torsion bar of spring steel by way of serration method.
 3. The structure as defined in claim 2, wherein the inner end of said axle is formed with a hitching jaw.
 4. The structure as defined in claim 2, wherein said axle and a boss of said base arm mounted toward an outer end of said axle are coupled by a key.
 5. The structure as defined in claim 2, wherein a cover having a larger diameter than the axles is mounted by a fastening means toward an external end surface of said axle.
 6. The structure as defined in claim 2, wherein the body is formed at an inner side thereof with a grease passage, and a grease hole is formed at appropriate place of the body for grease to be poured into the grease passage, and sealings adhered to the axles are installed at both inner sides of the body.
 7. A role decreasing structure of a commercial vehicle for the front and dead axles, comprising: a torsion bar configured with a first straight end and a second straight end; a torsion bar case configured to couple either said first straight end or said second straight end of said torsion bar with an inner end of an axle; at least one base arm having a first end configured and dimensioned to couple to a wheel and a boss coupled between a second end of said base arm and an external end of said axle by a key; and at least one mounting member defining a hole therethrough configured to receive said axle and couple toward said external end thereof, and wherein said mounting member has a first end configured to couple with a vehicle and a second end configured to couple with said base arm.
 8. The role decreasing structure of claim 7, wherein said axle is a dead axle of a commercial vehicle.
 9. The role decreasing structure of claim 7, wherein said axle is a front axle of a commercial vehicle.
 10. The role decreasing structure of claim 7, wherein said axle has an inner end formed with a hitching jaw.
 11. The role decreasing structure of claim 7, further comprising a cover having a larger diameter than said external end of said axle and configured to receive said external end of said axle.
 12. The role decreasing structure of claim 7, wherein said mounting member is configured to receive seals associated with said axle where said axle passes through said hole in said mounting member, and wherein said mounting member has a grease hole providing access to a grease passage.
 13. The role decreasing sturcture of claim 7, further comprising a coil spring coupled between said second end of said mounting member and said second end of said base arm. 